1. Field of the Invention
The present invention generally relates to a computer telephony integration adapter, and more specifically, to a network interface card (NIC) capable of utilizing existing analog telephone systems, as well as digital and serial bus connected telephone systems, such as a Universal Serial Bus (USB), for computer-based telephone applications.
2. Discussion of the Related Art
Many homes and businesses utilize two separate networks in order to handle computer data and telephone data. The telephone systems used in many organizations run on a dedicated network, such as a private branch exchange (PBX), that is de-coupled from the data network, such as a local area network (LAN) or the Internet. The cost for maintaining two separate networks for voice and data access is high. The typical cost of operating a PBX connection in a large business for a single employee is about $1,000 per year. Additionally, the PBX and the handsets coupled thereto are generally part of a closed architecture system that prevents open-market competitive products.
Use of a computer system, e.g., a personal computer (PC), to place telephone calls over a network connection such as the Internet, is becoming more popular. PC-based telephone applications may utilize special telephone systems, such as Internet Protocol telephones (IP phones) or software-based IP phones, in order to place calls over the Internet. IP phones, however, differ from existing analog telephone systems and digital telephone systems. Therefore, in order for a large organization to utilize PC-based telephone applications, new IP phones must be purchased and re-deployed throughout the organization. Moreover, an IP phone requires power from a main power outlet, or that the host computer system to which it is connected be activated and operational to provide power and other functionality to the IP phone. An IP phone may also derive power from the network if the network and the IP phone are properly equipped to do so.